Each ALD Dual Time is powered by dual Swiss quartz Ronda movements, operated by a pair of crowns, one on each side of the case. That keeps the case thickness at an extremely wearable 6.1 millimeters. The stone dials remain differentiators, and there are a couple of different configurations. The dual stone options feature tiger eye and black marble, or bloodstone and lapis, for each handset. In contrast, the ‘monolithic’ options utilize single stone dials in malachite, lapis lazuli, and aventurine, with sunray-finished matching subdials at 3 o’clock to enhance readability.